我使用org.apache.commons.net.ftp.FTPClient实现了

java代码将文件上传到服务器

对于多个文件,ftp上传速度非常慢.

我怎样才能提高速度.

– 改变图书馆？

用于上传多个文件的强大FTP客户端类库是什么？

– 使用多个线程？

如何用多线程实现ftp上传功能？

有人能告诉我一个例子吗？

我是多线程编程的新手.

在我阅读完所有答案后,我尝试更改我的代码并进行测试.

以下是一个示例FTPClient代码：

// create instance of FTPClient

FTPClient ftp = new FTPClient();

ftp.setControlEncoding("UTF-8");

ftp.setDefaultTimeout(30000);

// connect to server

try

{

ftp.connect("10.1.1.1", 990);

}

catch(Exception e)

{

System.out.println("Cannot connect to server");

return;

}

// login to server

if (!ftp.login("username", "password"))

{

ftp.logout();

System.out.println("Cannot login to server");

return;

}

try

{

ftp.setFileTransferMode(FTP.BINARY_FILE_TYPE);

ftp.enterLocalPassiveMode();

// ftp.setBufferSize(0);

}

catch(Exception e)

{

}

// create directory on server

// dirs is list of required directories on server

for (String dir : dirs)

{

try

{

ftp.makeDirectory(dir);

}

catch(IOException e)

{

}

}

// files is a map of local file and string of remote file

// such as

// file on client is "C://test/a.txt"

// location on server is "/test/a.txt"

for (Map.Entry entry : files.entrySet())

{

File localFile = entry.getKey();

String remoteFile = entry.getValue();

FileInputStream input = null;

try

{

input= new FileInputStream(localFile);

ftp.storeFile(remoteFile, input);

}

catch (Exception e)

{

try

{

ftp.deleteFile(remoteFile);

}

catch (IOException e1)

{

}

}

finally

{

if (input != null)

{

try

{

input.close();

}

catch (IOException e)

{

}

}

}

}

// disconnect

if (ftp != null && ftp.isConnected())

{

try

{

ftp.disconnect();

}

catch (IOException f)

{

// do nothing

}

}

当我上传1050个文件(每个文件大约1-20 KB)时,它花了大约49406 – 51000毫秒(这只是上传时间).

我想提高速度.

有人建议我使用ftp4j,但是当我用1050个文件测试库时,ftp4j的上传速度比FTPClient慢大约10000毫秒.

花了大约60000毫秒.

以下是示例ftp4j代码：

// create instance of FTPClient

FTPClient ftp = new FTPClient();

ftp.setCharset("UTF-8");

// connect to server

try

{

ftp.connect("10.1.1.1", 990);

}

catch(Exception e)

{

System.out.println("Cannot connect to server")

return;

}

// login to server

try

{

ftp.login("username", "password");

}

catch (Exception e)

{

try

{

ftp.logout();

}

catch (Exception e1)

{

}

System.out.println("Cannot login to server")

return;

}

try

{

ftp.setType(FTPClient.TYPE_BINARY);

ftp.setPassive(true);

}

catch(Exception e)

{

}

// create directory on server

// dirs is list of required directories on server

for (String dir : dirs)

{

try

{

ftp.createDirectory(dir);

}

catch (Exception e)

{

}

}

// files is a map of local file and string of remote file

// such as

// file on client is "C://test/a.txt"

// location on server is "/test/a.txt"

for (Map.Entry entry : files.entrySet())

{

final File localFile = entry.getKey();

final String remoteFile = entry.getValue();

BufferedInputStream input = null;

boolean success = false;

try

{

input = new BufferedInputStream(new FileInputStream(localFile));

// ftp.upload(localFile);

ftp.upload(remoteFile, input, 0, 2048, new MyTransferListener());

success = true;

}

catch (Exception e)

{

}

finally

{

if (input != null)

{

try

{

input.close();

}

catch (IOException e)

{

}

}

if (!success)

{

try

{

ftp.deleteFile(remoteFile);

}

catch (Exception e)

{

}

}

}

}

// disconnect

if (ftp != null && ftp.isConnected())

{

try

{

ftp.disconnect();

}

catch (IOException f)

{

// do nothing

}

}

我尝试使用多个线程.

以下是多线程代码：

final CountDownLatch latch = new CountDownLatch(files.size());

ExecutorService pool = Executors.newFixedThreadPool(10);

for (Map.Entry entry : files.entrySet())

{

final File localFile = entry.getKey();

final String remoteFile = entry.getValue();

pool.execute(new Runnable() {

public void run()

{

FileInputStream input = null;

try

{

input= new FileInputStream(localFile);

ftp.storeFile(remoteFile, input);

}

catch (Exception e)

{

try

{

ftp.deleteFile(remoteFile);

}

catch (IOException e1)

{

}

}

finally

{

if (input != null)

{

try

{

input.close();

}

catch (IOException e)

{

}

}

latch.countDown();

}

}

});

}

try

{

// waiting for all threads finish

// see: https://stackoverflow.com/questions/1250643/how-to-wait-for-all-threads-to-finish-using-executorservice

latch.await();

}

catch(Exception e)

{

}

这是对的吗？它工作正常,但无法提高速度.

它花了大约49000 – 51000毫秒与没有线程的代码相同.

我用内联网测试速度.互联网需要更多时间.

我该怎么做才能提高上传速度？